<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <meta http-equiv="X-UA-Compatible" content="ie=edge">
    <title>Document</title>
</head>

<body>
    <script>
        // 原型模式
        function Car(obj) {
            function Fn() {
                this.age = 987
            }

            obj.__proto__ = new Fn()

        }

        var obj = {
            name: "123"
        }
        Car(obj)
        console.log(obj)
    </script>
</body>

</html>